[pypy-dev] plans for the peg parser in pypy 3.9

[Carl Friedrich Bolz-Tereick]

Hi all,

so I've been hacking on getting an rpython version of the new peg parser
that cpython introduced in 3.9, and switched exclusively to in 3.10. My
status on the py3.9-peg-parser branch is that I managed to build a full
pypy-c with the new parser for the first time today, but there are still
a number of bugs (in particular, the interactive console is pretty broken).

I wanted to keep you in the loop on my plans for further steps:

- I plan to fix the bugs, obviously ;-)

- CPython made it possible to switch between the old and the new parser
in 3.9 with an environment variable. Unless somebody gives extremely
strong reasons for also having that feature, I would like to focus on
using the new parser exclusively. Being able to switch is quite a big
hassle, and I don't see it buying a lot.

- That said, I intend to keep the "parser" module functional for 3.9,
like CPython did. It will be removed (for us and for them) in 3.10.

Let me know if you are unhappy with that approach!

Cheers,

Carl Friedrich